exxon valdez oil spill restoration project final report · 2009. 5. 7. · exxon valdez oil spill ....
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Exxon Valdez Oil Spill
Restoration Project Final Report
Final 2005-2006 LTEMP Oil Monitoring Report Restoration Project 050763
James R. Payne, Ph.D. Payne Environmental Consultants, Inc.
1991 Village Park Way, Suite 206 B Encinitas, CA 92024
760-942-1015 [email protected]
William B. Driskell 6536 20th Avenue NE
Seattle, WA 98115 206-522-5930
Jeffrey W. Short, Ph.D. and Marie L. Larsen Auke Bay Laboratories
Alaska Fisheries Science Center, NOAA Fisheries Ted Stevens Marine Research Institute
17109 Point Lena Loop Road Juneau, AK 99801
907-789-6065 [email protected]
Prepared for Joe Banta
Project Manager Prince William Sound Regional Citizens' Advisory Council
3709 Spenard Road Anchorage, Alaska 99503 907/277-7222 or 273-6225
December 2008
T
3-1 Attachment
PWSRCAC Contract 951.06.01 he opinions expressed in this commissioned report
are not necessarily those of PWSRCAC
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Exxon Valdez Oil Spill Restoration Project Final Report
Final 2005-2006 LTEMP Oil Monitoring Report
Restoration Project 050763
James R. Payne, Ph.D. Payne Environmental Consultants, Inc.
1991 Village Park Way, Suite 206 B Encinitas, CA 92024
760-942-1015 [email protected]
William B. Driskell 6536 20th Avenue NE
Seattle, WA 98115 206-522-5930
Jeffrey W. Short, Ph.D. and Marie L. Larsen Auke Bay Laboratories
Alaska Fisheries Science Center, NOAA Fisheries Ted Stevens Marine Research Institute
17109 Point Lena Loop Road Juneau, AK 99801
907-789-6065 [email protected]
Prepared for Joe Banta
Project Manager Prince William Sound Regional Citizens' Advisory Council
3709 Spenard Road Anchorage, Alaska 99503 907/277-7222 or 273-6225
December 2008
PWSRCAC Contract 951.06.01 The opinions expressed in this commissioned report
are not necessarily those of PWSRCAC
2nd cover page
The Exxon Valdez Oil Spill Trustee Council administers all programs and activities free from discrimination based on race, color, national origin, age, sex, religion, marital status, pregnancy, parenthood, or disability. The Council administers all programs and activities in compliance with Title VI of the Civil Rights Act of 1964, Section 504 of the Rehabilitation Act of 1973, Title II of the Americans with Disabilities Act of 1990, the Age Discrimination Act of 1975, and Title IX of the Education Amendments of 1972. If you believe you have been discriminated against in any program, activity, or facility, or if you desire further information, please write to: EVOS Trustee Council, 441 West 5th Avenue, Suite 500, Anchorage, Alaska 99501-2340; or O.E.O. U.S. Department of the Interior, Washington D.C. 20240.
Study History Preceding this EVOS Trustees Restoration Project, the Long Term Environmental Monitoring Program (LTEMP) began in 1993 as a mandate in the charter of the Prince William Sound Regional Citizen’s Advisory Council (PWSRCAC). Aspects of the monitoring program have changed through the years, but mussel tissues are still being sampled biannually at ten fixed locations in Port Valdez, Prince William Sound, and along the outer coast from Seward to Kodiak in addition to subtidal sediments from two sites within Port Valdez. In 2004, joint funding was acquired from the Trustees along with an expansion in program objectives in 2005-2006 to include 1) sampling at random locations of EVOS impact (in addition to the original ten fixed LTEMP sites) to assess lingering oil and 2) exploration of oil levels at human habitation sites and extent of Monterey formation residues (from the 1964 earthquake). Peer-reviewed annual reports, datasets, and program reviews can be obtained from the PWSRCAC with the most recent publications available on their website, www.pwsrcac.org. Abstract The Long Term Environmental Monitoring Program (LTEMP) has been sampling mussels (and some sediments) twice annually at ten sites in Port Valdez, Prince William Sound, and nearby Gulf of Alaska sites since 1993. Samples are analyzed primarily for polycyclic aromatic and saturated hydrocarbons (PAH and SHC). Indices quantify the proportions of a hydrocarbon signal into dissolved, particulate/oil, and pyrogenic phases. After 1999, a decreasing trend appears in total PAH (TPAH) with current values below 100 ng/g dry weight (and many below 50 ng/g). Most currently measured samples reflect a predominantly dissolved-phase signal. This new low in TPAH likely represents ambient background levels. Furthermore, peaks and lows in total PAH trends and the similarities of the hydrocarbon signatures portray regional-scale dynamics. The five inner Prince William Sound sites have similar composition and behave similarly and yet are different from the three Gulf of Alaska sites. The Disk Island site has recently shown trace amounts of petrogenic signal from buried EVOS oil. The two Port Valdez sites are primarily influenced by the treated ballast water discharge from the Alyeska Marine Terminal.
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Key Words Alaska Exxon Valdez oil spill oil monitoring PAH Prince William Sound Northern Gulf of Alaska intertidal marine Mytilus trossulus sediments hydrocarbon chemistry
Project data Current and historical data for this program are maintained by the PWSRCAC LTEMP contractors and supplied along with metadata to the EVOS Trustees. Annual reports and the data are available on request and generally carried on the website, www.pwsrcac.org. Citation Payne, James R., William B. Driskell, Jeffrey W. Short, Marie L. Larsen. 2008. Final 2005-2006 LTEMP Oil Monitoring Report, Exxon Valdez Oil Spill Restoration Project Final Report (Restoration Project 050763), Prince William Sound Regional Citizen’s Advisory Council, Anchorage, Alaska. 137 pp.
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PRINCE WILLIAM SOUND RCAC Long-Term Environmental Monitoring Program
Final 2005-2006 LTEMP Monitoring Report
Photo by Dave Janka, 2005
James R. Payne, Ph.D. William B. Driskell Jeffrey W. Short, Ph.D. Marie L. Larsen
December 2008
T
PWSRCAC Contract 951.06.01he opinions expressed in this commissioned report are not necessarily those of PWSRCAC
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TABLE OF CONTENTS
1 Executive Summary ................................................................................................ 1 2 Introduction............................................................................................................. 3 3 Scope....................................................................................................................... 4 4 Methods................................................................................................................... 4
4.1 Sampling Design ................................................................................................ 4 4.2 Analytic Methods ............................................................................................... 6 4.3 Quality Assurance ............................................................................................ 11 4.4 Determination of Moisture Content ................................................................. 11 4.5 Particle Grain Size Determination.................................................................... 11 4.6 Determination of Total Organic and Total Carbon .......................................... 12 4.7 Data Analysis ................................................................................................... 12
4.7.1 Hydrocarbon Indices................................................................................. 13 4.7.2 Data Anomalies......................................................................................... 20
4.8 Data Management............................................................................................. 23 5 Results and Discussion ......................................................................................... 23
5.1 Sampling and Data Quality .............................................................................. 23 5.1.1 ABL Quality Assurance Chemistry Results ............................................. 23 5.1.2 Mussel Populations ................................................................................... 24
5.2 Port Valdez Sediments ..................................................................................... 24 5.2.1 Sediment Particle Grain Size .................................................................... 26 5.2.2 Total Organic and Inorganic Carbon ........................................................ 29 5.2.3 Sediment Chemistry.................................................................................. 30
5.2.3.1 Alyeska Marine Terminal ..................................................................... 32 5.2.3.2 Gold Creek ............................................................................................ 32 5.2.3.3 Constantine Harbor ............................................................................... 34
5.2.4 Summary and Discussion of Sediment Chemistry Results....................... 35 5.3 Mussel Tissue Chemistry ................................................................................. 37
5.3.1 Regional Trends and Approaches ............................................................. 37 5.3.2 Port Valdez Stations.................................................................................. 41
5.3.2.1 Alaska Marine Terminal Mussel Tissue Chemistry.............................. 41 5.3.2.2 Gold Creek Mussel Tissue Chemistry .................................................. 45
5.3.3 Prince William Sound Stations ................................................................. 46 5.3.3.1 Disk Island Mussel Tissue Chemistry................................................... 47 5.3.3.2 Knowles Head, Sheep Bay, and Sleepy Bay Mussel Tissue Chemistry51 5.3.3.3 Zaikof Bay Mussel Tissue Chemistry................................................... 56 5.3.3.4 Constantine Harbor Mussel Tissue Chemistry ..................................... 58
5.3.4 Gulf of Alaska Stations............................................................................. 60 5.3.4.1 Aialik Bay Mussel Tissue Chemistry ................................................... 60 5.3.4.2 Shuyak Harbor and Windy Bay Mussel Tissue Chemistry .................. 63
5.3.5 Summary and Discussion of Tissue Chemistry Results ........................... 68 6 Conclusions........................................................................................................... 71 7 References............................................................................................................. 72 8 Appendices............................................................................................................ 79
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Appendix A LTEMP Oil Primer.................................................................................. 80 A.1 Regional Sources.................................................................................................... 80 A.2 Oil Chemistry, Source Allocations, and Weathering Behavior ............................. 80 A.3 Mussels as Indicator Organisms ............................................................................ 87 Appendix B-1 TPAH and TSHC summary table for Alyeska Marine Terminal and
Gold Creek sediment samples, 1993-2006....................................................... 89 Appendix B-2 Summary of Sediment TPAH and component fractions, 1993-2006. . 93 Appendix C Tissue TPAH and TSHC summary for LTEMP 2005-2006. .................. 99 Appendix D – PAH plots from the 2005-2006 Tissue Analyses ................................ 102 Appendix E – Oiled Sediment and Mussel Histogram Plots from the 2005 GEM
Random Pit Sampling Program...................................................................... 113 Appendix F – Nordic Viking Diesel Spill................................................................... 132
LIST OF FIGURES
Figure 1 Map of the 2005/2006 LTEMP sites. .................................................................. 5 Figure 2 PAH profiles of oil droplets removed by filtration (upper) and the dissolved-
phase (lower) of the AMT BWTF effluent, January 2005 (from Payne et al. 2005b).................................................................................................................................... 15
Figure 3 SHC profiles of oil droplets removed by filtration (upper) and the dissolved-phase (lower) of the AMT BWTF effluent, January 2005 (from Payne et al. 2005b).................................................................................................................................... 16
Figure 4 Examples of PAH profiles from LTEMP mussels containing primarily background dissolved-phase components (analytes colored turquoise; top – Knowles Head) and particulate/oil-phase components from a diesel spill (colored gold; middle – Gold Creek), and LTEMP sediments containing primarily low-level combustion products (colored fuchsia; bottom – Gold Creek). White colored analytes are indeterminate. The fractional proportions of each phase (soluble, particulate/oil, and pyrogenic) are shown by the numbers in the upper right-hand corner of each plot with the number of analytes assigned to each group just below (e.g., the bottom replicate was 84% pyrogenic from the 24 fuchsia-coded analytes).......................... 18
Figure 5 PAH procedural artifact patterns (left graphs) common in early LTEMP samples between March 1993 and March 1997. For these samples, homolog data are incomplete. The overlaying solid lines with the blue diamonds represent reported MDLs. Line gaps indicate analytes not reported at the time. SHC analyses (right graphs) were discontinued between 1995 and 1998 due to lipid interference problems.................................................................................................................... 21
Figure 6 Representative PAH profiles and method detection limits (solid lines with blue diamonds) from July 1997 tissue samples showing highly similar procedural patterns (GC/MS integration artifacts – see Figure 5) plus additional naphthalenes. ............ 22
Figure 7 Time series and time overlays of grain size composition at Alyeska Marine Terminal and Gold Creek, 1993-2006. Sediments were not collected in 1998-99.. 27
Figure 8 Average fine sediment fractions (silt + clay) time series trends (±standard error of means) from GOC and AMT surficial sediment grabs. Note y-axis scale has been clipped for detailed viewing. Sediments were not collected in 1998-99. ................ 28
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Figure 9 Time series of total organic and inorganic carbon in AMT and GOC sediment. Dotted lines indicate data gaps. ................................................................................ 30
Figure 10 Time series TPAH and relative phase composition of PAH profiles in AMT and GOC sediment samples. Sediments were not collected in 1998-99.................. 31
Figure 11 PAH and SHC profiles from representative AMT sediment in July 2005 and March 2006 showing complex, oil/particulate-dominated signatures in a heavily weathered and biodegraded, mixed signal. MDLs indicated with dotted solid line.33
Figure 12 PAH and SHC data for July 2005 and March 2006 Gold Creek sediments.... 34 Figure 13 PAH and SHC histogram profiles from representative intertidal sediments
collected from Constantine Harbor. The line connecting the blue diamonds represents the sample-specific MDL. ....................................................................... 35
Figure 14 Mytilus TPAH time series (triplicate averages) for all LTEMP stations, 1998-2006........................................................................................................................... 38
Figure 15 Regional LTEMP Mytilus TPAH time series, 1998-2006............................... 39 Figure 16 Time series TPAH and relative phase composition of PAH profiles in Alyeska
Marine Terminal (AMT) and Gold Creek (GOC) Mytilus tissues. Dotted connecting lines without symbols indicate questionable data..................................................... 40
Figure 17 PAH and SHC profiles showing low-level TPAH with variable source signals (combustion-, dissolved-, and oil/particulate-phase) in AMT mussel samples collected in July 2005, October 2005 and March 2006, respectively. MDLs indicated with dotted solid line. ................................................................................ 42
Figure 18 PAH Phase assignments for AMT and GOC mussel samples with other data removed to facilitate visualization of alternating seasonal (winter vs. summer) spikes in dissolved and particulate phases. .......................................................................... 43
Figure 19 Gold Creek mussel PAH and SHC profiles showing low-level TPAH with mixed and variable source signals (combustion products with some particulate/oil-phase components) in July 2005 and March 2006 and a predominant dissolved-phase pattern in October 2005. MDLs indicated with dotted solid line. ................. 47
Figure 20 Time series TPAH and relative phase composition profiles in Disk Island (DII) Mytilus tissues. Dotted connecting lines without symbols indicate questionable data.................................................................................................................................... 48
Figure 21 Disk Island Mytilus PAH and SHC profiles showing low-level particulate/oil-phase components in July 2004, March 2005, and March 2006. MDLs indicated with dotted solid line................................................................................................. 49
Figure 22 Trace of fresh sheen of EVOS oil from disturbed sediments on Disk Island (above the LTEMP transect), July 2008. .................................................................. 50
Figure 23 Time series TPAH and relative phase composition profiles in Knowles Head (KNH), Sheep Bay (SHB), and Sleepy Bay (SLB) Mytilus tissues. Dotted connecting lines without symbols indicate questionable data. ................................. 52
Figure 24 Synchrony in average phase portions between Sheep Bay (SHB), Knowles Head (KNH), and Sleepy Bay (SLB) Mytilus PAH since July 1998........................ 53
Figure 25 Representative Knowles Head, Sheep Bay and Sleepy Bay Mytilus PAH and SHC profiles showing low-level particulate/oil-phase components in July 2004. MDLs indicated with dotted solid line...................................................................... 54
Figure 26 Representative Knowles Head and Sheep Bay Mytilus PAH and SHC profiles showing the return to trace-level dissolved-phase components at both sites in July
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2005, and the possible (below-MDL) shift to more of a mixed-phase particulate/oil- and combustion-product pattern at Sheep Bay in March 2006. MDLs indicated with dotted solid line......................................................................................................... 55
Figure 27 Representative Sleepy Bay Mytilus PAH and SHC profiles showing trace-level dissolved- and mixed-phase patterns in July 2005 and March 2006. The SHC profile in July 2005 is difficult to assess, but the March 2006 profile shows above-MDL marine biogenic and heavily weathered petrogenic components. MDLs indicated with dotted solid line................................................................................................. 56
Figure 28 Time series TPAH and relative phase composition profiles in Zaikof Bay (ZAB) Mytilus tissues. Dotted connecting lines without symbols indicate questionable data....................................................................................................... 57
Figure 29 Representative Constantine Harbor Mytilus and adjacent intertidal sediment PAH and SHC profiles from samples collected as part of the EVOS Trustees SCAT program in July 2005 and March 2006. MDLs indicated with dotted solid line. .... 59
Figure 30 Time series TPAH and relative phase composition profiles in Aialik Bay (AIB) Mytilus tissues. Dotted connecting lines without symbols indicate questionable data....................................................................................................... 61
Figure 31 Representative Aialik Bay Mytilus PAH and SHC profiles showing a mixed dissolved- and particulate/oil-phase pattern in March 2005, dissolved-phase components in July 2005, and mixed dissolved- and combustion-phase components in March 2006. The SHC profiles show just-below MDL traces of biogenic and petrogenic components in March 2005, with less-than MDL marine and terrestrial biogenic input in July 2005 and March 2006. MDLs indicated with dotted solid line................................................................................................................................... 62
Figure 32 Time series TPAH and relative phase composition profiles in Shuyak Harbor (SHH) and Windy Bay (WIB) Mytilus tissues. Dotted connecting lines without symbols indicate questionable data........................................................................... 64
Figure 33 Synchrony of Mytilus PAH phases between Shuyak Harbor (SHH) and Windy Bay (WIB) since July 1998. Correlations significant at p<0.001 and p< 0.02, df=14.................................................................................................................................... 65
Figure 34 Representative Shuyak Harbor Mytilus PAH and SHC profiles showing a trace-level particulate/oil-phase signal in August 2004 and dissolved-phase patterns in March and July 2005 and March 2006. The higher-molecular-weight n-alkane SHC profiles support the petrogenic PAH phase assignments in August 2004, but not the dissolved-phase pattern in March 2005. The July 2005 and March 2006 SHC profiles suggest biogenic marine input. ........................................................... 66
Figure 35 Representative Windy Bay Mytilus PAH and SHC profiles showing a trace-level particulate/oil-phase signal in August 2004 and dissolved-phase patterns in March and July 2005 and March 2006. The SHC profiles support the petrogenic PAH phase assignment in August 2004, but are contradictory in the March 2005 sample. Note that the SHC profiles in August 2004 and March 2005 are very similar to those observed at Shuyak Harbor (Figure 34) as well. MDLs indicated with dotted solid line......................................................................................................... 67
Figure 36 Average Mytilus TPAH time series and trend lines comparing Prince William Sound and Gulf of Alaska stations’ trends. .............................................................. 69
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Cover photo by David Janka off M/V Auklet showing 2005 pit-digging field crew (left to right): Jeff Short, Bill Driskell, Jim Payne, Clayton Payne, and Wyatt Fournier.
LIST OF TABLES
Table 1. LTEMP Stations 2005-2006. Reported station depths are not tidally corrected. 6 Table 2. Polycyclic aromatic hydrocarbon (PAH) and saturated hydrocarbon (SHC)
analytes measured in this study, along with analyte abbreviations, internal and surrogate standards...................................................................................................... 7
Table 3. Hydrocarbon Parameters Used in the LTEMP Data Analysis........................... 14 Table 4. Field notes on mussel populations, July 2005-March 2006. ............................. 25 Table 5 Total organic and inorganic carbon in sediment replicates at Port Valdez and
Constantine Harbor stations...................................................................................... 29 Table 6 Exact one-tailed probabilities of seasonal phase dominance in mussels at AMT
and GOC, 1993-2005 using randomization paired t-tests (1000 trials, n = 13)........ 42 Table 7 Detrended correlations of PAH phases between Sheep Bay (SHB), Knowles
Head (KNH), and Sleepy Bay (SLB) Mytilus tissue, July 1998-March 2006. ......... 51 Table 8 Current TPAH concentrations in mussel tissues (ng/g dry wt) relative to recent
NOAA Mussel Watch monitoring data and another recovered Alaskan oil-spill event.......................................................................................................................... 70
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LIST OF ABBREVIATIONS Stations:
AMT Alyeska Marine Terminal, Port Valdez AIB Aialik Bay, west of Seward COH Constantine Harbor, Hinchinbrook Entrance, PWS DII Disk Island, Knight Island Group, western PWS GOC Gold Creek, Port Valdez KNH Knowles Head, eastern PWS SHB Sheep Bay, eastern PWS SHH Shuyak Harbor, Kodiak SLB Sleepy Bay, Latouche Island, western PWS WIB Windy Bay, Outer Kenai Peninsula ZAB Zaikof Bay, Montague Island, central PWS
ABL NOAA/NMFS Auke Bay Laboratory, Juneau AK AHC aliphatic hydrocarbons (same as saturated hydrocarbons – SHC) ANS Alaskan North Slope BWTF Alyeska Terminal’s Ballast Water Treatment Facility DSI Dissolved Signal Index EVOS Exxon Valdez oil spill EVTHD Exxon Valdez Trustees Hydrocarbon Database EMAP US EPA Environmental Monitoring and Assessment Program GC/FID gas chromatography/flame ionization detector GC/MS gas chromatography/mass spectrometry GERG Geochemical and Environmental Research Group, Texas A&M University KLI Kinnetic Laboratories, Inc., Anchorage AK MDL analytic method detection limit NIST National Institute of Standards and Technology NMFS National Marine Fisheries Service NOAA National Oceanographic and Atmospheric Administration PAH polycyclic (or polynuclear) aromatic hydrocarbons PECI Payne Environmental Consultants, Inc., Encinitas, CA PGS particle grain size PSI Particulate Signal Index PWS Prince William Sound SHC saturated hydrocarbons (same as AHC: n-alkanes + pristane and phytane) SIM selected ion monitoring SRM NIST standard reference material TAHC total AHC TIC total inorganic carbon TOC total organic carbon TPAH total PAH TSHC total saturated hydrocarbons (same as total alkanes) UCM unresolved complex mixture
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1 Executive Summary From the 2005-06 LTEMP samplings, average tissue hydrocarbon levels remained at trace levels similar to those in recent years (max 61, min 9 ng/g dry weight, ppb). Even the Port Valdez stations, while still reflecting what appears to be very low levels of weathered particulate oil (presumably from the BWTF), continued to report concentrations around 50 ppb. Port Valdez sediments accumulated slightly higher levels, ~70 ppb. The trace levels seen at sites beyond Port Valdez doubtlessly reflect, oil-wise, the currently pristine nature of the environment. Furthermore, while the dissolved character of the signals points inconclusively to an unknown source(s), the broad-scale similarities suggest incidental geographic input rather than point sources. The only exception to this scenario occurs at the Disk Island site where mussels show a very low but more complex signature that suggests a weathered particulate/whole oil source. Normally, this signature would be too low to identify a source but in all likelihood, it is probably linked to residual EVOS oil seen buried above the transect in 2007 and 2008. In summary, the LTEMP program is primed for the mission of detecting spill events. In Port Valdez, we see the low-level imprint of human activities in addition to discharge from the Terminal, while elsewhere, we see the trace, dissolved-phase, background signal from an unknown source(s). Any new hydrocarbon inputs to the system have been and will be easily detected. This year, the program included a new component. Under the auspices of the EVOS Trustees Program, Long-term Monitoring of Anthropogenic Hydrocarbons in the Exxon Valdez Oil Spill Region (050763), ten intertidal sites within the Naked-Knight-Southwest Island complex were examined during the 2005 summer program to measure the extent of buried oil still present 16 years after the spill. At EVOS sites previously designated as heavily oiled, a number of random-stratified pits were dug to a depth of ~0.5 m to look for residual oil. Where available, mussels were also collected. Sediments and mussels were analyzed using LTEMP analytical protocols. The results have been published (Short et al., 2007a) and a separate report is being prepared by Dr. Jeffrey Short for this survey plus continuation studies completed in 2006 and 2007. As part of PWSRCAC efforts, PAH and SHC sample profiles are included in Appendix E. Briefly, TPAH levels in the oiled pits ranged from a low of 42 ng/g (on Knight Island) to a high of 567,000 ng/g (on Latouche Island) with the buried oil showing varying states of weathering (from extensively degraded to very fresh). The mussel samples collected from these same beaches (but not necessarily immediately adjacent to the oiled pits) showed low (11 to 42 ng/g dry weight) dissolved-phase TPAH signals very similar to those observed at the traditional LTEMP stations. Although there were still persistent buried EVOS residues at a number of the beaches, they are highly sequestered and do not appear to be bioavailable unless disturbed. Rates of disappearance have diminished to an estimated 4% yr-1. If left undisturbed, Short et al. predict they will be there for decades.
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Also attached to this report are the results from chemical analyses of mussel and sediment samples collected in Olsen Bay after the F/V Nordic Viking diesel spill in July 2007 (Appendix F). The three October 2007 mussel samples show a low-level, weathered diesel signal (698-1,169 ppb) while the single sediment sample showed very low (2.4 ppb) diesel components. Prior to delving into the rich technical details of the report, readers unfamiliar with environmental hydrocarbon chemistry may want to examine Appendix A, a primer on basic hydrocarbon chemistry, weathering patterns, and using mussels as indicator organisms.
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